The classification states that the graphs are certain cyclic covers of the 3-dimensional cube
\(Q_3\)  or among a list of seventeen exceptional graphs all of which are in the Foster census
[1]}. Using magma [2]} it turns out that \(\mathcal {M}_O(16,3,9)\)  is
the only graph of the seventeen exceptions isomorphic to a feasible \(\mathcal {M}_O(n,a,b)\) 
graph. Because this graph is arc-transitive, it is of course not \(\mathcal {F}(1,2)\) -invariant and thus
has to be excluded from the collection \(\mathcal {C}\)  from Theorem 2.1. However, as the parameters of this
graph in fact satisfy item 5 in the last group on page 4, which is due to our results in Section 8, this
graph already will be excluded from \(\mathcal {C}\)  this way, and so there is no need to mention it separately.
This is the first convoluted situation mentioned in the outline of the proof at the end of Section 2.
